you believe businesses should be allowed to refuse mixed race couples? - no!
I believe bakers should be allowed to refuse to bake customised wedding cakes for mixed-race couples who are getting married. Then people will choose other, more open-minded bakers and the bakers will lose business. They'll be punished organically rather than by fiat.
This should be about equal protection. And we do need laws to specifically state that. What if you're a black couple in an extremely racist town? And I have seen those in the south. Where even the coffee shop in the middle of town is called the Koffee Kup Kafe (KKK) and clan rallies are held in the park in the middle of town.
Going to another baker? There may not be another one in a small town. And being the minority, is it going to hurt his business to boycott the baker? Probably not. In fact, other racists might hear of it and stop in to congratulate him and patronize his shop as a thank you. No. Going to another baker or advertising his bigotry isn't going to ruin a baker in many cases. Just like when our president makes highly corrupt appointees and does business with them. The corruption, like the racism, isn't the bug, to them, it's the feature.
Look at Chick-fil-A. Their anti gay practices caused a wave of Christians to patronize them even more. So much for your idea.
The reason many racist practices were stopped is the government forced them to stop. The job of the government is to protect equal rights for ALL, not just the majority. Your "organic" solution could have taken hundreds of years.
Not buying it.
But, like SBF says, a lot of this bigotry is going away. The country is becoming more tolerant. And Christianity is on the decline too. Yes, there will still be pockets of people that are the result of mental inbreeding. I don't know if I'll see it all gone in my lifetime. But then again, I never expected to see gay marriage legalized. Nor pot legalized in so many states. We could reach a tipping point to where all of this old thinking just washes away!